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    97 Products

    Heavy-Profile Nylon-Insert Locknuts
    3D CAD models available

    Image of Product. Front orientation. Locknuts. Heavy-Profile Nylon-Insert Locknuts .
    About 10% wider and taller than standard-profile locknuts, these handle heavier loads by distributing them over a larger area. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp.
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    1/2"3/8"250° F100000000000000000
    5/16"-18
    9/16"7/16"250° F10000000000000000
    3/8"-16
    11/16"35/64"250° F5000000000000000
    7/16"-14
    3/4"39/64"Not Rated2500000000000000
    1/2"-13
    7/8"45/64"250° F2500000000000000
    5/8"-11
    1 1/16"55/64"250° F1000000000000000
    3/4"-10
    1 1/4"1"250° F50000000000000
    7/8"-9
    1 7/16"1 1/8"250° F500000000000000
    1"-8
    1 5/8"1 17/64"250° F10000000000000
    1 1/4"-7
    2"1 41/64"250° F10000000000000
    1 1/2"-6
    2 3/8"1 59/64"250° F100000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    316 Stainless Steel—Our most corrosion-resistant nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/4"-20
    1/2"3/8"250° F1000000000000000
    5/16"-18
    9/16"7/16"250° F50000000000000
    3/8"-16
    11/16"35/64"250° F50000000000000
    1/2"-13
    7/8"45/64"250° F10000000000000
    5/8"-11
    1 1/16"55/64"250° F10000000000000
    3/4"-10
    1 1/4"1"250° F100000000000000
    7/8"-9
    1 7/16"1 9/64"Not Rated100000000000000
    1"-8
    1 5/8"1 5/16"Not Rated100000000000000
     
    316 Stainless Steel
    3/8"-16
    11/16"35/64"250° F100000000000000
    1/2"-13
    7/8"45/64"250° F10000000000000
    5/8"-11
    1 1/16"55/64"250° F100000000000000
    3/4"-10
    1 1/4"1"250° F100000000000000
     

    Thin-Heavy-Profile Nylon-Insert Locknuts
    3D CAD models available

    Image of Product. Front orientation. Locknuts. Thin-Heavy-Profile Nylon-Insert Locknuts.
    About half the height of standard-profile locknuts and 10% wider, these fit in spaces with low clearance and handle heavier loads by distributing them over a larger area. You can also use them as jam nuts by threading them against a hex nut to hold it in place. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    High-Strength Steel
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Black Phosphate-Coated Steel—The dark coating creates both a finished appearance and a barrier against rust that's comparable to zinc yellow-chromate plating.
    Steel—These locknuts are best for dry environments since moisture will cause them to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert
    Max.
    Temp.
    Each
    Black Phosphate-Coated Steel
    1 1/4"-12
    2"1 7/64"ASTM Grade C
    250° F00000000000000
    1 1/2"-12
    2 3/8"1 5/16"ASTM Grade C
    250° F0000000000000
    1 3/4"-12
    2 3/4"1 15/32"ASTM Grade C
    250° F00000000000000
    2"-12
    3 1/8"1 43/64"ASTM Grade C
    250° F00000000000000
    2 1/4"-12
    3 1/2"1 15/16"ASTM Grade C
    250° F00000000000000
    2 1/2"-12
    4"2 3/16"ASTM Grade C
    250° F00000000000000
    2 3/4"-12
    4"2 3/16"ASTM Grade C
    250° F00000000000000
    3"-12
    4 1/2"2 41/64"ASTM Grade C
    250° F000000000000000
     
    Steel
    1 1/8"-12
    1 7/8"1"ASTM Grade C
    250° F00000000000000
    1 3/8"-12
    2 13/64"1 3/16"ASTM Grade C
    250° F00000000000000
     
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Black Corrosion-Resistant-Coated Steel—These nuts combine a finished appearance with the rust resistance of stainless steel. The coating has been tested to extreme standards, including 1,000 hours of salt spray resistance, to hold up in wet and outdoor environments. Also known as black luster.
    Thread
    Size
    Wd.
    Ht.
    Insert
    Max.
    Temp.
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    1/2"9/32"250° F100000000000000000
    5/16"-18
    9/16"5/16"250° F10000000000000000
    3/8"-16
    11/16"13/32"250° F5000000000000000
    1/2"-13
    7/8"17/32"250° F2500000000000000
    5/8"-11
    1 1/16"39/64"250° F1000000000000000
    3/4"-10
    1 1/4"45/64"250° F1000000000000000
    1"-8
    1 5/8"57/64"250° F10000000000000
    1 1/4"-7
    2"1 7/64"250° F10000000000000
     
    Black Corrosion-Resistant-Coated Steel
    1/4"-20
    1/2"9/32"250° F50000000000000
    5/16"-18
    9/16"5/16"250° F50000000000000
    3/8"-16
    11/16"13/32"250° F10000000000000
    1/2"-13
    7/8"17/32"250° F10000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    316 Stainless Steel—Our most corrosion-resistant nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Insert
    Max.
    Temp.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/4"-20
    1/2"9/32"250° F25000000000000000
    5/16"-18
    9/16"5/16"250° F2000000000000000
    3/8"-16
    11/16"13/32"250° F1000000000000000
    1/2"-13
    7/8"17/32"250° F10000000000000
    5/8"-11
    1 1/16"5/8"250° F10000000000000
    3/4"-10
    1 1/4"45/64"250° F100000000000000
    1"-8
    1 5/8"59/64"250° F100000000000000
     
    316 Stainless Steel
    3/8"-16
    11/16"13/32"250° F10000000000000
    1/2"-13
    7/8"17/32"250° F10000000000000
    5/8"-11
    1 1/16"39/64"250° F10000000000000
    3/4"-10
    1 1/4"45/64"250° F100000000000000
     

    Heavy-Profile Flex-Top Locknuts for Heavy Vibration
    3D CAD models available

    Image of Product. Front orientation. Locknuts. Heavy-Profile Flex-Top Locknuts for Heavy Vibration.
    About 10% wider and taller than standard flex-top nuts, these handle heavier loads by distributing them over a larger area. The top section expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. As a result, they're suitable for use in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Steel
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    1/4"-20
    1/2"19/64"10000000000000000
    5/16"-18
    9/16"21/64"1000000000000000
    3/8"-16
    5/8"25/64"1000000000000000
    1/2"-13
    13/16"1/2"500000000000000
    5/8"-11
    1"41/64"10000000000000
    3/4"-10
    1 1/8"49/64"10000000000000
    7/8"-9
    1 5/16"57/64"100000000000000
    1"-8
    1 1/2"1 1/64"100000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/4"-20
    1/2"19/64"1000000000000000
    5/16"-18
    9/16"21/64"100000000000000
    3/8"-16
    5/8"25/64"100000000000000
    7/16"-14
    3/4"29/64"100000000000000
    1/2"-13
    13/16"1/2"100000000000000
     

    Thin-Heavy-Profile Flex-Top Locknuts for Heavy Vibration
    3D CAD models available

    Image of Product. Front orientation. Locknuts. Thin-Heavy-Profile Flex-Top Locknuts for Heavy Vibration.
    About two-thirds the height of standard flex-top nuts and 10% wider, these fit in spaces with low clearance and handle heavier loads by distributing them over a larger area. Because of the thin profile, you can also use them as jam nuts by threading them against a hex nut to hold it in place. The top section expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. As a result, they're suitable for use in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Steel
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    1/4"-20
    1/2"7/32"25000000000000000
    5/16"-18
    9/16"17/64"100000000000000
    3/8"-16
    5/8"9/32"1000000000000000
    7/16"-14
    3/4"21/64"10000000000000
    1/2"-13
    13/16"21/64"500000000000000
    5/8"-11
    1"13/32"10000000000000
    3/4"-10
    1 1/8"27/64"100000000000000
    7/8"-9
    1 5/16"31/64"100000000000000
    1"-8
    1 1/2"37/64"100000000000000
     

    Heavy-Profile Steel-Insert Locknuts for Extreme Vibration
    3D CAD models available

    Image of Product. Bottom orientation. Locknuts. Heavy-Profile Steel-Insert Locknuts for Extreme Vibration.
    Nearly 10% wider and taller than standard steel-insert locknuts, these handle heavier loads by distributing them over a larger area. They also have the most secure hold of all the heavy-profile locknuts we offer. The tab on the insert stops the nut from rotating, even under extreme vibration. These locknuts are ideal for equipment with constant motion or jarring starts and stops, including conveyors, shakers, and compactors. You can even reuse them once or twice, but their holding power decreases with each use.
    High-Strength Steel
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc Yellow-Chromate-Plated Steel—With a more durable finish than clear zinc plating, these nuts are suitable for most wet and outdoor environments. However, they won't hold up to the harsh chemicals that stainless steel can.
    Steel—These locknuts are best for dry environments since moisture will cause them to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Each
    Zinc Yellow-Chromate-Plated Steel
    1/2"-13
    7/8"19/32"SAE Grade 8
    00000000000000
    5/8"-11
    1 1/16"47/64"SAE Grade 8
    0000000000000
    3/4"-10
    1 1/4"57/64"SAE Grade 8
    0000000000000
    1"-8
    1 5/8"1 11/64"SAE Grade 8
    00000000000000
     
    Steel
    3/8"-16
    11/16"13/32"SAE Grade 8
    0000000000000
    1/2"-13
    7/8"37/64"SAE Grade 8
    0000000000000
    5/8"-11
    1 1/16"47/64"SAE Grade 8
    0000000000000
    3/4"-10
    1 1/4"7/8"SAE Grade 8
    0000000000000
    7/8"-9
    1 7/16"1 1/32"SAE Grade 8
    00000000000000
    1"-8
    1 5/8"1 11/64"SAE Grade 8
    00000000000000
    1 1/8"-7
    1 13/16"1 17/64"SAE Grade 8
    00000000000000
    1 1/4"-7
    2"1 13/32"SAE Grade 8
    00000000000000
    1 1/2"-6
    2 3/8"1 11/16"SAE Grade 8
    00000000000000
    1 3/4"-5
    2 3/4"2 1/32"SAE Grade 8
    000000000000000
     
    Medium-Strength Steel
    These Grade 5 or Class 8 nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Steel—These locknuts are best for dry environments since moisture will cause them to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Each
    Steel
    1/2"-13
    7/8"9/16"SAE Grade 5
    00000000000000
    5/8"-11
    1 1/16"45/64"SAE Grade 5
    0000000000000
    3/4"-10
    1 1/4"27/32"SAE Grade 5
    0000000000000
    7/8"-9
    1 7/16"63/64"SAE Grade 5
    0000000000000
    1"-8
    1 5/8"1 1/8"SAE Grade 5
    00000000000000
     
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